The present invention concerns apparatus for generating electric current. It is particularly concerned with providing a compact and reliable generator which is readily portable. Such a generator can find many fields of application one of which would be for use in providing power for portable radios in environments where there is no provision of electrical mains.
It is, of course, well-known to provide generators driven by pedal power. These, of course, require continuous effort in order to be operational. A radio having a removable spring-powered generator has been disclosed in UK Patent Specification No. 2262324 filed by the inventor of the present application. However, it proved exceptionally difficult to put into practice the basic concept described in the above UK patent specification. Part of this difficulty was caused by the inherent problem of providing a low-cost gear train which could reliably transmit the substantial amount of energy stored in a powerful spring to an electrical generator whilst ensuring that the energy in the spring was released both controllably and at the correct rate.